A bulging vein or ateriovenous fistula that develops on the forehead relates to blood flow between arteries and veins. Sometimes these veins arise as a result of exercise, injury, or underlying health complication such as kidney problems. Bulging veins on the forehead may be characterized by swelling, reddishness, or take on a purplish hue. Treatment options can involve surgery, according to the Merck Manuals Online Medical Library.
According to Scientific American, escalating arterial pressure during exercise causes veins under the skin to rise closer to the skin's surface. Locations of the body where less fat exists under the skin such as the forehead tend to expose bulging veins more readily. See your doctor or health care practitioner if the bulging vein on your forehead remains visible following exercise.
A bulging vein may appear in the forehead as a result of a traumatic injury, according to the MayoClinic.com. An arteriovenous fistula represents an atypical connection between the artery and the vein; blood bypasses the normal route from arteries to capillaries to veins and instead flows directly from the artery to the vein. Any injury that penetrates the skin may activate an arteriovenous fistula. Speak to your doctor or health care practitioner if you have had a recent facial injury and notice a bulging vein in your forehead.
If left untreated, a bulging vein may instigate heart problems down the line, according to the Merck Manuals Online Medical Library. Large arteriovenous fistulas may induce a decrease in blood pressure, which in turn makes the heart work harder and may impede heart function over time.
Treatment for a bulging vein on the forehead depends on the size of the arteriovenous fistula, according to MayoClinic.com. In some cases, the bulging vein closes on its own; in others surgery becomes necessary.